The invention relates to a method for performing a jump starting operation or a remote charging operation of a recipient vehicle having a discharged high-voltage traction battery by means of a donor vehicle having a charged high voltage traction battery.
Owing to unfavorable circumstances, the situation may arise whereby a rechargeable battery of a hybrid vehicle used for starting the internal combustion engine via a high voltage network is empty or has such a low state of charge that continued travel is no longer possible. Hybrid vehicles generally do not have starter motors which can be operated on the conventional 12 volt vehicle electrical distribution system. In this case, this vehicle would need to be towed to the next charging station. The same situation can arise in the case of an electrically driven vehicle in which the rechargeable battery, i.e. the high-voltage traction battery, is empty or has such a low state of charge that continued travel is not possible.
WO 2011/026721 A2 relates to a jump starting method and a device for implementing this method. The method and the device relate to jump starting in the case of vehicles with an electric drive, wherein a vehicle has a discharged battery and another vehicle is used for jump starting. The two vehicles each comprise a rectifier and a DC to DC converter in order to charge the respective batteries thereof in the case of use with the public electric grid. In order to provide jump starting, the DC networks of the two vehicles are connected to one another via a cable. The required voltage matching and power control is in this case performed by the DC to DC converter of the vehicle expecting jump starting. In addition, it is disclosed that a connection between the control devices of the two vehicles is produced via the jumper cable in order to monitor the jumping operation. WO 2011/026721 A2 discloses a jump starting method in which a connection is produced between the control devices of the two vehicles involved.
DE 10 2004 008 817 A1 relates to a method and an apparatus for charging a battery using two voltage electrical systems. The high voltage battery of a vehicle is charged via a jumper cable. The vehicle comprises two DC networks, namely a 42 volt network for driving a starter/generator and furthermore a 12 volt network for operating the lighting and the remaining electrical or electronic systems. The starter/generator is used to start the motor of the vehicle. If this vehicle is intended to be jump started, the 12 volt battery is connected to a jumper cable. In this case, the high voltage battery of the vehicle can be charged via a DC-to DC converter.
US 2008/0100259 A1 discloses a jump starting apparatus as its subject matter. Said jump starting apparatus is connected to the high-voltage battery and the battery management system of a vehicle. The apparatus comprises converters for drawing the electrical energy required for charging either from the public electric grid or from other sources, for example from a 12 volt source.
JP 2009 154847 A relates to a control device for a vehicle with a hybrid drive. This vehicle comprises a high voltage battery and an auxiliary battery. Suitable devices are provided for charging the high voltage battery with the aid of the auxiliary battery, wherein this charging operation is monitored by a control device.
In the case of hybrid vehicles or in the case of electric vehicles, it should be taken into consideration that, in the case of a vehicle with an operation ready battery, some of the energy of said battery can be output to a vehicle which is not operation ready so that continued travel of the latter vehicle to the next charging station is possible. The resultant problem is the fact that differently charged batteries or batteries with a different maximum voltage cannot be connected directly since the currents resulting from the voltage difference are only limited by the resistance of a connection between the two vehicles. For this reason, the currents occurring are much too high or even impossible owing to the different voltage potentials between the batteries.